Method of injecting fuel into internal-combustion engines and apparatus therefor



W. RFEHM METHOD OF INJECTING FUEL INTO INTERNAL COMBUSTION ENGINES ANDAPPARATUS THEREFOR Filed Feb. 28, 1922 l/V VENTOR H A TTOR/VE V5 x [TEDSTATES PATENT orri Patented May 13, 1924.

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WIIiHELM RIEHM, OF AUGSBURG, BAVARIA. GERMANY, ASSIGNOR TO THEMASCHINENFABRIK AUGSIBURG-NUERNBURG, G-ESELLSCHAFT, OF AUGSBURG,"

GERMANY, A CORPORATION OF GERMANY.

METHOD OF INJECTING FUEL INTO INTERNAL-COMBUSTION ENGINES AND APPAEKATUS THEREFOR.

Application filed February 28, 1922. Serial No. 539,906.

T 0 all whom it may concern Be it known that I, TILHELM RIEHM, a citizenof Germany, residing at. Augsburg, Stadtbachstrasse 7, State of Bavaria,Germany, have invented certain new, and useful Improvements in Methodsof Injecting Fuel into Internal-Combustion Engines and ApparatusTherefor: and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

The present invention relates to the injection of fuel into thecylinders of internal combustion engines, and has to doparticularly withthe injection of heavy fuels which must be associated with a lighterfuel in order to effect satisfactory ignition.

In the use of heavy oils, or similar fuels having a relatively highignition point, it is common to employ a secondary fuel, preferably alighter hydrocarbon of relatively low igniting temperature, for thepurpose of attaining an initial combustion in the engine cylinder togenerate a temperature sufficiently high to ignite the heavier fuel. Thetwo fuels are commonly injected inclependently through separateopenings. This process of ignition is, however, subject to certaindisadvantages, such as frequent failure of the heavy-fuels to ignite,due to the fact that the burning of the "ignition fuel heats the gaseswithin the engine cylinder locally to a temperature sufficiently high tocause ignition of the principal fuel, but does not raise the temperatureof the entire cylinder to such a degree. Consequently, an excessiveamount of the lighter ignition fuel must be used so that the temperatureat all parts of the cylinder is sufliciently high to ignite theprincipal fuel. Furthermore, it is necessary that the ignition fuel beinjected somewhat previous to the injection of the main fuel, so thatcombustion may be well under way at the time of the principal injection.To satisfactorily employ the above system of ignition relativelycomplicated fuel injection apparatus is required, and an unduly largeamount of ignition fuel is con sumed.

It has also been proposed to admit both fuels through the same injectionnozzle. Such a method has proven satisfactory in effecting reliableignition of the fuel, but after a relatively short time of operationleads to accumulation of asphalt or similar tarry deposits within theinjection valve and upon the parts of the cylinder adjacent this valve.Furthermore, at the end of the main injection operation the injectionnozzle is filled with the heavy fuel. At the begin ning of thesucceeding injection period, when it is desired to first force thelighter ignition fuel into the cylinder, the nozzle must first be freedof the residual fuel from the preceding injection period. Thus aconsiderable quantity of heavy fuel finds its way prematurely into thecylinder and is deposited upon the cylinder walls without beingcompletely burned or, at best, is only inefficiently utilized.

It is a principal object of the present invention to provide a methodfor ignition.

of heavy fuels in the cylinders of internal combustion engines in aconvenient and efficient'manner, which avoids the above mentioneddifficulties. 7

More specifically, it is ,an object of the invention to effectsatisfactory ignition in a system of the above type in which theignition fuel and working fuel are independently injected into thecylinder, the working fuel being passed directly to the hottest portionof the combustion chamber.

It is a still further object to provide an apparatus for carrying outthe above method in a convenient and satisfactory manner.

I have illustrated a preferred embodimentof my invention in theaccompanying drawing, which is a vertical sectional view, somewhatdiagrammatic, showing an internal combustion engine cylinder embodyingmy improved apparatus.

Referring to the drawing, 1 indica tw the wall of the engine cylinderprovided with the usual inwardly extending member 2, which carries theparts of the injection valve. The inject-ion nozzles are preferablyformed in an independent cap member a normally secured in position atthe lower end of the member 2 by threaded ring 9' having an inwardlyextending annular flange g for engaging a cooperating flange provided atthe periphery of member a. t

The supporting member 2 is traversed longitudinally by'f-uel passages eand leadcylinder may be direct the jet of'heavy jet of ignition fuelandfit) around the member 0:.

ing from the supply reservoirs for the ignition fuel andheavierfoperating fuel, re-

spectively. I'liave illustrated a single passage for each of the twofuels, but it is obvious that any desired number of such passages may beemployed. The fuel passage 6 is in. communication. with a plurality ofinjection nozzles d spaced concentrically Fuel may be admitted to thepassage e and the injection nozzles d by any well known method, notshown, and is injected into the cylinder along a course approximatelyindicated by the dotted line d.

ignite at a point The injection of thetwo fuels may occursimultaneously, or the ignition fuel may be admitted slightly before theprincipal fuel, if desired.

While I have indicated that the injection nozzles b and dconsist of aplurality of openings uniformly spaced around the memher a, it isobvious that any other arrangement may be employed. I preferably em ployone ignition fuel nozzle to each nozzle for the injection of the heavierfuel, as

shown.

While I have illustrated a preferred embodiment of apparatus forcarrying out my improved method, it is understood that va- Undcr theparticularconditions' of operation the jet d of fuel \Ylll riousmodifications may be made in the details of construction and arrangementof parts without departing from the spirit of the invention, as definedin the appended claims;

I I claim:

1. Fuel injection apparatus for internal combustion engines, comprisingmeans for projecting an ignition fuel to the engine cylinder along dverging paths, and independent means for in ecting diverging ets ofworking fuel directly to the point of ignition of said ignition fuel.

2. Fuel injection apparatus for internal combustion engines, comprisinginlets for projecting diverging jets of ignition fuel into theeng-inecylinder, and a plurality of inlets for introducing diverging jets ofworking fuel into the cylinder at angles to said first jets, said fueljets intersecting at substantially the point of ignition of the ignitionfuel.

3. Fuel injecting apparatus for internal combustion engines, comprisinginlets for projecting diverging jets of ignition fuel into the enginecylinder, and a plurality of independent openings for introducingworking fluid into the cylinder at angles to said first jets, said fueljets intersecting at substantially the point of ignition of the ignitionfuel.

4. Fuel injection apparatus for internal. combustion engines, comprisinga plurality of inlets for admitting jets for ignition fuel to the enginecylinder, and a plurality of cooperating inlets for introducing jets ofworking fuel into the cylinder directed respectively to the ignitionpoints of the several jets of ignition fuel.

In testimony whereof I affix my signature.

WILHELM RIEHM.

Witnesses:

ALEXANDER DE S0'ro, ALEXETS Pi-nnrrrorr.

